If you were out protesting and thought you might get arrested there was a card you could carry round that would remind you, and the police, of your rights. Handy little thing in the right circumstances.
I found a ‘certificate’ I must have filled in to get into a club/pub in 1984. I was not 18 at the time and I assume I didn’t look it so was asked to fill it in. I think I called my self Maria because that is one name I get called, still to this day, when someone can’t pronounce my name. The Paddington address would have been believable as I had friends living in the suburb.